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Maurice Poirier
2005-03-10, 12:20
Will the power supply in SB2 cause interference with AM reception like it does in SB1?

seanadams
2005-03-10, 13:07
It's the same power supply. FWIW we do have our own in-house EMI
measurement setup - antennas, spectrum analyzer, calibration equipment,
the whole nine yards. SB2 is definitely quieter than SB1, including the
low freq AM band, because of extensive power supply isolation (which
was done to optimize DAC performance).

All electronic devices emit some EMI. I can not say for certain whether
anyone will have issues in a particular setup with a particular radio
listening to a particular radio station. What I can tell you is that
both Squeezebox and Squeezebox2 pass FCC/CE levels by WIDE margins and
the system as a whole (power supply included) is certified by an
independent lab (Pulver Labs in Los Gatos, CA) as required by FCC.
That doesn't mean there are zero emissions, it means they're very low.

As I said before, our PS vendor is investigating possible improvements.
If you want to use a different power supply you may. We recognize it
should be improved, but we don't consider this a fatal defect in the
power supply since:

i) it passes worldwide EMI requirements just fine
ii) the vast majority of our customers prefer the small design
iii) very few (specifically, about one in two thousand) customers have
encountered any interference at all. I realize that is no consolation
if you *are* affected, I am merely explaining the situation.



On Mar 10, 2005, at 11:20 AM, Maurice Poirier wrote:

> Will the power supply in SB2 cause interference with AM reception like
> it does in SB1?
>